<p>Substance use disorders (SUDs) are increasing globally, and social support as well as access to substance-free activities are essential for sustained recovery. Mental health services should therefore be effective, accessible, and supportive of psychosocial functioning. The aim of this scoping review was to map the extent of research examining psychosocial outcomes associated with group-based physical activity among individuals with SUDs and to identify psychosocial factors reported to enhance the reinforcing value of such activities. In addition, the review assessed the extent to which included studies emphasized interaction, communication, cooperation, and group cohesion, and whether interventions were delivered alongside other psychosocial treatments. Following PRISMA-ScR guidelines, searches were conducted in MEDLINE, PsycINFO, Scopus, and the Cochrane Library for publications from 2010 to 2025. Eighteen studies met the inclusion criteria. Across studies, psychosocial factors such as structured and inclusive environments, professional guidance, perceived autonomy, and social support were commonly reported as contributing to engagement and positive psychosocial outcomes associated with group-based physical activity. However, relatively few studies explicitly emphasized group-level processes, and most interventions were delivered in combination with other psychosocial treatments, limiting the ability to isolate group-specific effects. This review highlights a knowledge gap concerning the social components of group-based physical activity interventions and their role in shaping psychosocial outcomes among individuals with SUDs.</p>